ReadonlybitsValidity bits, LSB-first, already carrying [0, from).
Exposed so an op can write a run of cells as bytes rather than
through RangeOutput.set per cell; most ops want set.
ReadonlyvaluesLength to. [0, from) already carries the previous output.
Marks a cell missing.
Only needed to undo a RangeOutput.set made in the same
pass. Cells in [from, to) start unset and an unwritten cell
seals as missing, so clearing one the op never set does nothing —
which is why an empty clear passed the whole suite until a
set-then-clear case was written (Layer 2, PR #573).
Marks a cell present, with its value.
A writable output buffer for a ranged recompute — [PND-PROCRANGE].
The rows an op keeps unchanged are already here, values and validity, copied as blocks. The op fills
[from, to)and nothing else.This exists because carrying a prefix forward correctly is harder than it looks and the obvious shortcut is silently wrong. Packed storage holds
0at a missing cell, notNaN, so copying onlyvaluesturns every warm-up gap in the prefix into a defined zero — measured at 1,875 wrong cells on a 5-study pass, caught by a from-scratch comparison rather than by any type. Validity has to move with the values, and doing that per cell is theO(n)walk the whole ticket exists to remove.